9.3. Catch-all addresses

A catch-all address is one that, in the absence of a mailbox with that exact name, receives all mail for the domain in which it resides.

So, if the accounts and and exist, and mail comes in for , it goes to that mailbox.

Mail for is handled by the account. This may be a forward or even a mailbox.

To retrieve mail from a catch all mailbox, either use login '*@example.com' or plain 'example.com' or even 'whatever@example.com'.